In a typical prior art head and disk system a magnetic transducer is supported by the suspension as it flies above the disk. The magnetic transducer, usually called a “head” or “slider” is composed of elements that perform the task of writing magnetic transitions (the write head) and reading the magnetic transitions (the read head). The surface of the slider which confronts the media is patterned with features that control the air-bearing characteristics. The disk is attached to a spindle that is driven by a spindle motor to rotate the disk at sufficient speed to develop the air-bearing. In the typical process of fabricating thin film magnetic transducers, a large number of transducers are formed simultaneously on a wafer. After the basic transducer structures are formed the wafer may be sliced into rows or individual sliders which typically are further processed by lapping and formation of the air-bearing surface features by lithographic etching techniques.
FIG. 1 illustrates the ABS of slider 20 which is conventionally fabricated with a pattern of rails 26, 27 that extend toward the media from the slider body to determine the aerodynamics and serve as the contact area should the slider come in contact with the disk either while rotating or when stationary.
In prior art stamp lithography, stamps have been fabricated by casting polydimethylsiloxane (PDMS) on a master with a negative of the desired pattern. The PDMS stamp is peeled away from the master after curing and exposed to an “ink” transferred to the substrate by transient contact with the stamp. The elastomeric nature of the PDMS allows contact even on rough or curved surfaces. According to this method, features between 1 and 100 microns are achieved. For larger stamps and larger features (1 cm to 200 microns), the pattern is directly etched into the stamp by conventional UV lithography using a mild soap solution for dissolving those regions previously exposed to the UV light. When applying this method to lithography with submicron features, it was found that no reproducible results necessary for mass-production of ICs were attainable with a type of stamp as propagated by Kumar et al. A major limitation of this method of pattern transfer is the elastomer used as the carrier of the pattern. This material is deformable so that repeated, accurate transfer of the pattern to the substrate with high resolution, as necessary for practical lithography, is not possible.
In U.S. Pat. No. 5,817,242 to Biebuyck, et al. use of a composite stamp is described that includes a deformable or elastic layer for conformal contact, accommodating the fluctuations of the thickness of the substrate and impurities on its surface, and a second (patterned) layer, which carries the desired pattern. Suitable materials for the deformable or elastic layer are said to be polybutyldiene, polydimethylsiloxane (PDMS), polyacrylamide, polybutylstyrene and co-polymers of these types. The patterned layer should easily adhere to or absorb a specific “ink” material. Suitable materials could be organic, such as polystyrene or polymethylmethacrylate, metallic, such as gold, platinum, palladium, nickel, titanium and oxides thereof, or inorganic insulators like alumina, silicon, silica, or perovskites, depending on the desired properties and application. In a further preferred embodiment, the stamp comprises means for achieving a self-alignment. The means could either comprise key-and-lock type topological features, e.g. cone- or pyramid-shaped protrusions and holes, which after a sufficiently accurate pre-positioning by stepping drives guide the stamp into the desired final position. A preferred means for self-aligning the stamp and the substrate however exploits surface tension gradients provided on the surface of the stamp and/or substrate.
In U.S. Pat. No. 6,094,805 to Iijima, et al., a method for manufacturing a magnetic head is described using a resist sheet (an organic resist film on a supporting body) which is placed on the air bearing surface to transfer the resist film on to the air bearing surface, after which, the supporting body is removed. The supporting body is a flexible film, constituted of polyethylene terephthalate or the like.
In U.S. Pat. No. 4,564,585 to Balske, et al., a process for applying photoresist to a row of sliders is described. The row of sliders is mounted in a fixture by bonding with an adhesive. The slider row extends 1 mil. above the fixture surface. The fixture and row are inserted between two rollers of a laminating machine. The upper roller pressure applies a sheet of dry film photoresist material so that it adheres as a layer on the row.